Grinding machinery



Z W g J L A J 0 14 w I 20 61, J4 L Filed Feb. 5. 1930 2 Sheets-Sheet 1 6km: 4 V012 Aug; 16, 1932. 5. A. VOLZ 1,371,856

7 GRINDING MACHINERY Filed Feb. 5, 1950 2 Sheets-Sheet 2 mun n Patented Aug. 16, 1932 UNITED STATES PATENT OFFICE GEORGE A. VOLZ, OI CINCINNATI, OEIO, ASSIGNOB 1'0 CINCINNATI GRINDEBS INCOR- POBA'I'ED, GINGINNA'I'L-OEIO, A CORPORATION: OF OHIO eamnme maomnax Application filed February 1980. Serial No. 426,118.-

This invention relates to improvements in machine tools andespecially to improvements in centerless grinders.

A11 object of the invention is to provide 5 improved means for forming and finishing Tpherical work pieces such as balls and the ike.

Another object of the invention is the provision of a machine particularly adapted for the production of spherical articles which will automatically impart a gyratory or twisting movement to the workpiece to insure proper presentation of its entire surface to the grinding orforming member.

provision of a mechanism of the centerless type which will substitute for the normal constant directional urge of the work piece a continuously varying resultant thrust component insuring satisfactory generation of spherical .or like surfaces on the work.

Other objects and advantages of the present invention should be readlly apparent. by reference to the following specification considered in conjunction with the accompanying drawings forming a part thereof and it is to be understood that any modifications may be made in the specific structural details without departing from or exceeding the spirit-of the invention. f'

Figure 1 is a front elevation of a device embodying the improvements of this invention.

Figure 2 is a top plan view of the device shown in Figure 1.

Figure 3 is a sectional view taken on line 3-3 of Figure 1.

Figure 4; is a sectional view taken on line 4-4 of Figure 2.

Figure 5 is a fragmentary plan view of the regulatingwheel showing its relation to the Work and grinding wheel in one position.

Figure 6 is a view similar to Figure 5 showing the parts in the opposite position.

Figure 7 is a" fragmentary sectional view A further object of the invention is the ried by the upper slide 13. A screw 16 having pilot or hand wheel 17 on one end thereof is provided for adjusting the regulating wheel unit 14 toward and from the grinding wheel 18. The grinding wheel 18 is carried by the usual spindle j ournaled in housing 19 fixedly carried on the upper surface of the bed 10.

Truing mechanisms 20 and 21 are provided for forming and truing the active opposed surfaces of the grinding and regulating wheels. Grinding wheel 19 is rotated in a clockwise direction as indicated by the arrow on the housing thereof at a rapid rate of speed to effect a stock removal from the work piece. The regulating wheel 15is likewise rotated in a clockwise direction as indicated by the arrow but at a relatively slow rate of speed to control the rotation of the work piece. By this construction the opposed active faces of the wheels travel in opposite directions and the faces of the wheels form a grinding throat therebetween in which the work piece is placed.

The spindles 22 and 23 respectively sup porting the grinding wheel 18 and regulating wheel 15 are adapted to be rotated about axes extending in parallel planes. The grinding wheel 18 is mounted normal to its spindle 22 and rotates ina vertical plane while the regulating wheel 15 is canted so as to rotate in a plane at an angle to the plane of rotation of the axis of its spindle and to the plane of ro tation of the grinding wheel, as shown in i Figures 5 and 6 for example. The grinding and regulating wheels are respectively provided with grooves 24 and 25 rotating in tan.- dem in the same plane; but due to the angularly related planes of rotation of the grinding and regulating wheels the grooves form flanges 26 and 27 on the grinding wheel uninterrupted throughout the periphery thereof while interrupted flanges 28 and 29 are formed on the regulating wheel 15. The interrupted flanges 28 and 29 each have their enlarged or high portion opposite to the low portion of the other and the lateral dimension or cross-section of each flange varies from a feather edge or substantial point as at 28' and 29 to a flange having asubstantial cross sec tion of material as at 28a and 29a, illustrated in Figures 5 and 6. This construction results in cam faces 28b and 29b being formed respectively between points 28' and 28a and points 29 and 29a. A work rest blade or thrust member 30 is provided intermediate the wheels for supporting the work piece during grinding and to take up the thrust of the grinding wheel against the work piece. ThlS work rest blade 1s supported by a block 31 carried by the inner end of the lower slide 12. The operation of the grinding and regulating wheels is as follows:

The work piece being positioned on the blade 30 by means to be later described is brought into engagement with the active faces of the grinding and regulating wheels and is rotated by the frictional contact between itself and the wheels. The grinding wheel in addition effects a stock removal from the work piece and produces the proper finish thereon. The regulating wheel through its frictional engagement with the work piece controls the rotation thereof and at the same time through the cam faces 28b and 29?) engage the work piece or balls at a plurality of points during its rotation and exerts a thrust component on the ball either to the right or left intocontact with either flange 26 or 27 depending upon whether flange 28 or 29 is in engagement therewith. This results in a rotation of the ball about a multiplicity of axes between the various points of contact on the cams 28 and 29 and the opposed points of contact of flanges 26 and 27 about which the rotation of the work piece or ball 32 takes place, and since first one cam face and then the other cam face engages the balls a thrust component is first exerted on one side thereof gradually shifting to the center of the groove and then to the opposite side thereby presenting the entire surface of the work piece or ball to the grinding wheel to properly finish the surface of the ball and reduce same to a spherical form within a fractional part of a thousandth of an inch.

Any desired means may be provided for actuating the grinding and regulating wheels toward and from one another to feed the ball into the grinding wheel and as here shown comprises a cam 33 for rocking an arm 34 which has a pivoted connection at 35 with the feed screw 16 for axially shifting said screw and the regulating wheel unit connected therewith. To adjust the relative position of the faces of the wheels for size and to compensate for wheel wear the hand or pilot wheel 17 is employed as noted above.

To insert and remove a work piece from the grinding throat the following mechanism may be employed. Carried by the block 31 is a frame work or bracket 36 provided with a cylinder 37 in which a piston 38 is adapted to be reciprocated and has extending therefrom a piston rod 39. The upper end of the piston rod is secured to a tongue 40 carried by a slide 41 whereby the piston 39 alternately raises and lowers the slide 41. A housing 42 is secured to the bracket 36 and is provided with guide ways for the slide 41 as well as a magazine 43 for unfinished work pieces and a discharge trough 44 for finished work pieces.

The piston 38 is adapted to be hydraulical- 1y actuated and is coupled by pipes or conduits 45 and 46 with the infeed mechanism indicated generally by the numeral 47 so that the slide is actuated at the same time the grinding and regulating wheels have been retracted to their furtliermost position. A- detent 48 is provided being pivotally carried by the magazine 43 for preventing discharge of the work pieces therefrom except when the slide 41 is in the uppermost position to receive a new work piece. To effect the operation of the detent the slide 41 carries a pin 49 cooperating therewith to raise same about its pivot at the uppermost position of the slide. A work piece carrying member such as 50 shown in Figure 7 is provided for carrying the balls from the upper end or loadmg position to the lower end or grinding position of the housing 42 and this shelf is so formed to automatically discharge the work piece through the discharge chute 44 when raised and to receive an unfinished work piece thereon.

It is believed that the foregoing description clearly discloses an automatic ball grinder of the centerless type wherein a magazine is provided for unfinished work pieces or balls together with means for bringing the balls from the magazine to the grinding position and then discharging the balls therefrom. It should also be noted that by this construction spherical work pieces may be properly ground and finished throughout their entire surface to the desired degree of spherity and finish. This machine is especial- 1y adapted to be used'for finishing large size balls but may be used for any size ball with equal facility.

What is claimed is:

1. In a device of the class described, the combination of opposed grindin and regulating wheels forming a grin ing throat therebetween, each of the wheels having grooves therein rotatable in tandem in the same plane, thegrinding wheel groove being flanked on each side with an uninterrupted flange, the regulating wheel groove being flanked on each side with an interrupted flange means within the grinding throat for supporting the work piece during grinding and means for efli'ecting an approach andretraction of the wheels to feed the work-piece into the grinding wheel.

2. In a deviceof the class, described, the combination of opposed grindin and regulating wheels formin a grin, ing throat therebetween, each 0 the wheels having grooves therein rotatable in tandem in a vertical plane, the grinding Wheel groove being flanked on each side with an uninterrupted flan e, the regulating wheel groove being flan ed on each side with an interrupted flange means within the grinding throat for supporting the work piece during grinding, means for efiectin'g an approach and retraction of the wheels to feed the work piece into the grinding wheel, and means for placing in and removing a work piece from the grinding throat when the wheels are retracted.

3. In a device of the class described the combination of a work support, a grinding wheel rotatable at a high rate of speed, in a downward direction toward the work support, a regulating wheel rotatable in a direction with its active face traveling upwardly as respects the work support at a slow rate of speed, the grinding wheel being provided with a groove flanked on each side thereof with a flange, the regulating wheel being provided with a groove forming interrupted flanges to exert a controlling component on the work piece sequentially in opposite directions and automatic means for placing on and removing work pieces from the work support.

4. In a ball grinder the combination of a grinding member rotatable at a high or grinding rate of speed to effect stock removal from a work piece or ball, a regulating member frictionally engaging the ball to control the rate of rotation thereof, means integral with the regulating member exerting a lateral thrust component on the ball first in one direction and then in the opposite direction, means integral with the grinding member for opposing the lateral thrust, of the regulating member and cooperating therewith to effect a rotation of the ball about a plurality of axes, and means supporting the ball within the grinding throat during grindm E. In a ball grinder the combination of a grinding member rotatable at a high rate of speed to eflect stock removal from a work component on the ball first in one direction and thenin the opposite direction, means integral with the grinding member for opposing the lateral thrust of the regulating member and cooperating therewith to' effect a rotation of the ball abouta plurality of axes, means supporting the ball within the grinding throat during grinding and means slidably actuating the regulating member toward and from the grinding member to feed the work member.

6. In-a ball grinder, the combination of a grinding member rotatable at a high rate of speed to effect stock removal from a work piece or ball, a regulating member frictionally engaging the ball. to control the rate of rotation thereof, means integral with the regulating member exerting a lateral thrust component on the ball first in one direction and then in the opposite direction, means integral with the grinding member for opposing the lateral thrust of the regulating member and cooperating therewith to eflect a rotation of the ball about a plurality of axes, means supporting the ball within the grinding throat during grinding and means I for automatically loading an unfinished work piece on the work piece support and ejecting a finished work piece therefrom.

7. In a ball grinder, the combination of a grinding member rotatable at a high rate of speed to effect stock removal from a work iece or ball a re ulatin member frictionally engaging the ball to control the rateof rotation thereof, means integral with the regulating member exerting a lateral thrust component on the ball first in one direction and piecesagainst the said grinding then in the opposite direction, means integral with the grinding member for opposing the thrust of the regulating member and cooperating therewith to effect a rotation of the ball about a plurality of axes, means supporting the ball within the grinding throat during grinding, means automatically loading an unfinished work piece on the work piece support and ejecting a finished work piece therefrom and synchronizing means between the loading and e ecting means and the regulating member actuatingmeans' to efi'ect the loading and ejecting of the work when the regulating member is in a retracted position.

8. A machine of the character described including peripherally opposed work abrading and controlling members rotatable about parallel axes, one of said members being mounted in oblique'relation to its axis of rotation whereby a transverse shifting of the operative face of the oblique member with respect to the opposed member is effected during rotation of said obliquely disposed member.

9. In a grinding machine the combination with a spindle support of a spindle rotatably mounted therein, and an abrasive wheel mounted on the spindle in oblique relation to the axis of rotation thereof whereby the op erative surface of said Wheel will have both a movement of rotation and a traversing movement as respects any fixed point opposed to the periphery thereof during its rotation.

In testimony whereof I aflix my signature.

GEORGE A. VOLZ. 

